Firearm magazine adapter and release assembly

ABSTRACT

An exemplary firearm includes a magazine well including an adapter-receiving portion defining an adapter receiving-recess and a magazine adapter removably coupled to the adapter-receiving portion of the magazine well. The magazine adapter includes a magazine catch assembly configured to move between a magazine-engaging state and a magazine disengaging state.

REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/925,427 filed Jan. 9, 2014 and entitled “FIREARM MAGAZINE ADAPTER AND RELEASE ASSEMBLY” and U.S. Provisional Patent Application Ser. No. 62/090,122 filed Dec. 10, 2014 and entitled “FIREARM MAGAZINE ADAPTER AND RELEASE ASSEMBLY,” both of which are hereby incorporated by reference in its entirety.

BACKGROUND

Firearms include a receiver, an action, a trigger mechanism, and a barrel. The barrel is often secured to one end of the receiver. Often a magazine is coupled with the receiver in such a manner to allow the magazine to feed cartridges into position within a firing chamber formed in the barrel. Detachable magazines may allow an operator to rapidly change magazines. However, most firearms use a single type of cartridge and corresponding type of detachable magazine type. If use of a different type of cartridge is desired, another firearm is used, which may include different controls. Use of firearms with different controls may add not only additional equipment. expenses, but additional training expenses and time.

The subject matter claimed herein is not limited to embodiments that solve any disadvantages or that operate only in environments such as those described above. Rather, this background is only provided to illustrate one exemplary technology area where some embodiments described herein may be practiced.

BRIEF SUMMARY

An exemplary firearm includes a magazine well including an adapter-receiving portion defining an adapter receiving-recess and a magazine adapter removably coupled to the adapter-receiving portion of the magazine well. The magazine adapter includes a magazine catch assembly configured to move between a magazine-engaging state and a magazine-disengaging state.

An exemplary firearm includes a magazine release/retention assembly a first magazine release mechanism. The first magazine release mechanism includes a first release lever having a first end and a second end. A first transfer link coupled to the second end of the first release lever. The first transfer link being configured to removably couple to a magazine catch assembly. The magazine catch assembly is configured to move between a magazine-engaging state and a magazine-disengaging state. Actuation of the first release lever moves the magazine catch assembly toward the magazine-disengaging state. Release of the first release lever returns the magazine catch assembly to the magazine-engaging state. Such a magazine release/retention assembly includes a second magazine release mechanism. The second magazine release mechanism includes an ambidextrous transfer link, an ambidextrous release bar coupled to ambidextrous transfer link, and a second transfer link coupling the ambidextrous transfer link to the first transfer link, and the first release lever such that actuation of the ambidextrous release bar moves the magazine catch assembly toward the magazine-disengaging state. Release of the ambidextrous release bar returns the magazine catch assembly to the magazine-engaging state.

The subject matter claimed herein is not limited to embodiments that solve any disadvantages or that operate only in environments such as those described above. Rather, this background is only provided to illustrate one exemplary technology area where some embodiments described herein may be practiced.

BRIEF DESCRIPTION OF THE DRAWINGS.

To further clarify various aspects of some example embodiments of the present invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. It is appreciated that these drawings depict only illustrated embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:

FIG. 1A is an elevation view of a firearm according to one example;

FIG. 1B is an exploded view of the firearm of FIG. 1;

FIG. 2A is an exploded view of a primary magazine adapter according to one example;

FIG. 2B is a top view of a stock assembly having a primary magazine adapter coupled thereto;

FIG. 3 is a perspective view of a stock assembly and also illustrates a primary magazine adapter and magazine retention/release assembly according to one example;

FIG. 4A is an exploded view of a secondary magazine adapter according to one example;

FIG. 4B is a top view of a stock assembly having a secondary magazine adapter coupled thereto;

FIG. 5A is an elevation view of a firearm according to one example; and

FIG. 5B is an exploded view of the firearm of FIG. 5A.

DETAILED DESCRIPTION

Firearms are provided herein having at least one magazine adapter that will be described in more detail below and may include a magazine retention/release assembly that utilizes a plurality of magazine release mechanisms. Firearms may also accept multiple magazine adapters, which allows the firearm to use multiple calibers and to readily switch between calibers while using the same controls (such as the same trigger and magazine retention/release assembly) in the same configuration, which may make the firearm readily adaptable according to operator preferences or requirements with minimal additional training. Further, as will be discussed in more detail herein, multiple magazine release mechanisms may allow the operator to leverage training on other systems as one of the magazine retention/release mechanisms may be at a familiar location relative to the trigger and/or other components, such as the grip.

FIG. 1A illustrates an exemplary firearm 100. The firearm shown is configured as a rifle and as a semiautomatic bull pup rifle in particular. It will be appreciated that the magazine release assembly and the magazine adapter(s) set forth herein may also be integrated or used with other configurations Of firearms, including conventional firearm configurations such as conventional rifles and pistols, shotguns, or other configurations and other types of actions including bolt, lever, pump or other types of actions as desired.

The firearm 100 includes a receiver 1100 configured to couple or facilitate coupling of a barrel 1200 to an action 1300. In at least one example, the firearm 100 further includes a stock assembly 1400 coupled to the receiver 1100. It will be appreciated that the stock assembly 1400 may be partially or completely integrated with the receiver 1100 in some examples.

The action 1300 is configured to feed cartridges (which include a case, a primer coupled to the case, a powder charge, and a projectile) from a magazine 1500 (coupled to the receiver 1100 via the stock assembly 1400) into a chamber defined in the barrel 1200 and to extract spent cases therefrom. A trigger 1310 is coupled to the action 1300. When actuated, the trigger 1310 causes a firing pin associated with the action to strike the primer, thereby causing the primer to ignite and thereby causing the powder charge in the cartridge to burn. The burning powder generates pressure which drives the projectile from the muzzle of the barrel. As the action 1300 cycles or is cycled rearward, the action extracts and ejects the spent casing.

Components and parts of components will be described as being forward of other parts located more distally from the muzzle 1210. Relative position or movement toward the muzzle 1210 will be described as forward movement, and such position may be generally described as front or frontward. Similarly, components or parts of components winch are more distal from the muzzle 1210 will be described as being rearward of other elements located more proximal to the muzzle 1210, and such position will be described as rear locations.

The axial translations set forth herein will be understood to be generally parallel to an axis 1220 defined by a center of the barrel 1200. Lateral or transverse movement may be described with respect to any datum. In many instances described below, lateral movement is described with respect to a lateral sidewall 1110 of the receiver 1100.

The receiver 1100 may include a front portion 1120 configured to couple to and/or receive the barrel 1200. The receiver 1100 may also include a rear portion 1130, a top portion 1140, and a bottom portion 1150. As illustrated in FIG. 1A, the bottom portion 1150 of the receiver 1100 is configured to have a magazine 1500 coupled thereto. In particular, the magazine 1500 is coupled to the firearm 100 via the stock assembly 1400. More specifically, as will be discussed in more detail hereinafter, a primary magazine adapter 200 and a primary magazine retention/release assembly 300 are operatively associated with the stock assembly 1400 in such a manner that when the magazine 1500 is coupled to the firearm 100, the magazine 1500 feeds a loaded cartridge to the action 1300 and allows the action 1300 to cycle the loaded cartridge into the chamber defined in the barrel 1200 as introduced above. The magazine adapters disclosed herein, including the primary magazine adapter 200 may be coupled to or integrated with the stock assembly 1400, which is coupled to the receiver 1100, as shown. It will be appreciated that in other examples, the magazine retention/release assembly 300 may also be coupled to or integrated with a stock assembly 1400 or any other part or component.

As shown in FIG. 1B, the magazine 1500 includes opposing sidewalls 1520, 1525, a front portion 1530, and a rear portion 1540 that define a cartridge receiving recess. A top portion 1550 includes feed lips 1552 configured to further align and orient cartridges for feeding. A floor plate 1560 may be coupled to or integrated with a bottom portion of the magazine 1500. A follower 1570 is positioned between the feed lips 1552 and the floor plate 1560. A biasing member (such as a spring, not shown) is positioned between the follower 1570 and the floor plate 1560 and exerts a biasing force against the follower 1570 to urge the follower 1570 toward the feed lips 1552.

To load the magazine 1500, cartridges are inserted below the feed lips 1552 opposition to the biasing force acting on the follower 1570. Thus, cartridges loaded into the magazine 1500 are contained between the feed lips 1552 and the follower 1570. Each magazine, regardless of type, may be described with reference to a width dimension, a length dimension (which roughly corresponds to the length of a cartridge to be contained within such magazine) and a height.

As shown in FIG. 1B, the stock assembly 1400 generally includes a front portion 1410 and a rear portion 1420. In the illustrated example, the front portion 1410 is configured as a hand guard/heat shield. The rear portion 1420 shown includes as primary magazine well 1430 configured to have. various magazine adapters coupled thereto, including the primary magazine adapter 200. As will be discussed in more detail hereinafter, each of the various magazine adapters include a magazine catch assembly (sometimes also referred to as a mag catch plate) and a magwell adapter housing (sometimes also referred to as a mag insert plate) configured to allow the primary magazine well 1430 to receive a type of magazine corresponding to the type of magazine adapter that is coupled to the primary magazine well 1430.

Referring to FIGS. 1A-1B, in order to couple a first type of magazine, such as magazine 1500 to the firearm 100 the magazine 1500 is oriented for insertion. In at least one example, the magazine 1500 includes a protrusion or ridge 1542 associated with the rear portion 1540. In contrast, in some examples the front portion 1520 of the magazine 1500 may be generally flat. Generally, a profile of a magazine well and a magazine well opening corresponds to the outer profile or perimeter of the type of magazine the magazine well and the magazine well opening are configured to receive.

As such, the primary magazine well 1430 may have a channel 1470 defined therein to receive the protrusion or ridge 1542 on the rear 1540 of a primary type of magazine, such as magazine 1500. In such an example, if the magazine 1500 is oriented incorrectly, the ridge 1542 would interfere with a front portion 1462 (shown in FIG. 2B and discussed in more detail with reference thereto) of the primary magazine well 1430 thereby preventing coupling of the magazine 1500 to the primary magazine well 1430. If the magazine is oriented correctly, the ridge 1542 is aligned with respect to the channel 1470.

The top portion 1550 of the magazine 1500 may then be inserted into the primary magazine well 1430 via the magazine well opening 2600 (FIG. 2B). As a primary type of magazine, such as the magazine 1500, is thus inserted into the primary magazine well 1430, the primary magazine adapter 200 acts to retain the primary magazine 1500.

By way of introduction, the magazine 1500 has a mag catch receiving slot 1580 defined in one side 1520 thereof. Further, the magazine catch receiving slot 1580 defined in the side 1520 of the magazine 1500 may be located on the magazine 1500 such that the primary magazine catch tab 2230 (FIG. 2A) is urged into engaging contact with the magazine catch receiving slot 1580 when the magazine 1500 is sufficiently inserted into the primary magazine well 1430 to allow proper feeding from the magazine 1500. When the primary magazine catch tab 2230 (FIG. 2A) is thus urged into engagement with the magazine catch receiving slot 1580 in the magazine 1500, the magazine 1500 is retained in the primary magazine well 1430.

Magazine catch assemblies generally are configured to couple to the magazine retention/release assembly 300 (FIG. 1A). With a magazine catch assembly thus coupled to the magazine retention/release assembly 300, the primary and/or supplemental magazine releases may be actuated to release magazines coupled to the primary magazine well 1430 and a corresponding magazine adapter.

With reference now to FIG. 2A, the primary magazine adapter 200 will first be described generally. Thereafter, the general interaction of the primary magazine adapter 200 with the primary magazine well 1430 and the magazine retention/release assembly 300 will be described. Thereafter, the interaction one-type of secondary magazine adapter with the magazine retention/release assembly 300 and the primary magazine well 1430 will be described.

As shown in FIG. 2A, the primary magazine adapter 200 generally includes a primary magazine catch assembly 2000 and a primary magwell adapter housing 2500. The primary magazine catch assembly 2000 generally includes a primary magazine catch body 2100, a primary magazine catch arm 2200, and a primary mag catch release hook 2300.

The primary magazine catch body 2100 is configured to couple to the primary magazine well 1430 (FIG. 1B). The primary magazine catch body 2100 may be of any desired shape. In the illustrated example, the primary magazine catch body 2100 includes a front portion 2110, a rear portion 2115, a top portion 2120, a bottom portion 2125, a first or exterior sidewall 2130, and second or interior sidewall 2135. It will be appreciated the primary magazine catch body 2100 may have any shape desired. A mag catch opening 2140 is formed in the primary magazine catch body 2100 that extends through the first and second sidewall 2130, 2135 respectively.

The primary magazine catch body 2100 is configured to allow the primary magazine catch arm 2200 to move between a first, magazine engaging position and a second, magazine disengaging position. In the illustrated example, the primary magazine catch arm 2200 rotates between these positions. Accordingly, the primary magazine catch arm 2200 may include a first end 2210 pivotingly coupled to the primary magazine catch body 2100. In particular, a pin 2400 extends through holes 2112 defined in the first end 2110 of the primary magazine catch body 2100 and corresponding holes 2212 in the first end 2210 of the primary magazine catch arm 2200.

The primary magazine catch arm 2200 may also include a second end 2220 having a primary magazine catch tab 2230 associated therewith. In such an example, the primary magazine catch arm 2200 may be configured to rotate to thereby allow the second end 2220 of the magazine catch arm 2200 to rotate to allow the primary magazine catch arm 2200 to extend through the primary magazine catch opening 2140. The position of the primary magazine catch tab 2230 extending through the primary magazine catch opening 2140 and extending beyond the second sidewall 2135 in particular may correspond to the first, magazine engaging position introduced above. A biasing member 2240 may be included with the primary magazine catch assembly 2000 to exert a biasing force on the primary magazine catch arm 2200 to help maintain the primary magazine catch arm 2200 (and the primary magazine catch tab 2230 in particular) in the first, magazine engaging position.

As shown in FIG. 2A, the primary magazine catch arm 2200 further includes at least one catch arm actuation feature 2250 configured to transfer and/or translate inputs received from the magazine retention/release assembly 300 (FIG. 1A) into appropriate movement of the primary magazine catch arm 2200 from the first, magazine-engaged position toward the second, magazine disengaged position and from the second, disengaged position back toward the first, magazine disengaged.

In one example, the catch arm actuation feature 2250 includes a ramped surface positioned between the first and second ends 2210, 2220 of the primary magazine catch arm 2200. The ramped surface may be configured to interact with the primary mag catch release hook 2300.

The primary mag catch release hook 2300 may include a first end 2310 and a second end 2320. The first end 2310 and the second end 2320 may be offset from each other or extend in different directions as shown. in the illustrated example, the primary mag catch release hook 2300 generally has an L-shape. The first end 2310 of the primary mag catch release hook 2300 may include a release engagement feature 2330 configured allow the primary mag catch release hook 2300 to be selectively coupled and uncoupled to the magazine retention/release assembly 300, as will be described at an appropriate point hereinafter in more detail.

The second end 2320 of the primary nag catch release hook 2300 includes a mag catch engagement feature 2340. The mag catch engagement feature 2340 is configured to engage the catch arm actuation feature 2250 in such a manner that translation of the primary mag catch release hook 2300 moves the primary magazine catch arm 2200 between the first, magazine-engaged position and the second, magazine disengaged position.

In the illustrated example, the primary magazine catch release hook 2300 is at least partially received within a hook receiving channel 2350 defined in the second or interior sidewall 2135 of the primary magazine catch body 2100. The primary mag catch release hook 2300 is positioned relative to the primary magazine catch body 2100 in such a manner that the mag catch engagement feature 2340 extends outwardly through the interior sidewall 2135 of the primary magazine catch body 2100 and at least partially into the mag catch opening 2140.

The primary magwell adapter housing 2500 is configured to be coupled to the primary magazine catch body 2100 and to retain the primary mag catch release hook 2300 therebetween. In particular, the primary magwell adapter housing 2500 generally includes a first portion 2510 configured to couple to the primary magazine catch body 2100 and a second portion 2520 opposite the first portion. For example, the first portion 2510 includes a tab 2530 having a hole 2535 defined therein. The tab 2530 may be positioned relative to the primary magazine catch body 2100 to align the hole 2535 with the holes 2112, 2212 in the primary magazine catch body 2100 and the primary magazine catch arm 2200 respectively to allow the pin 2400 to pass therethrough thereby coupling the primary magwell adapter housing 2500 to the primary magazine catch body 2100.

The first portion 2510 of the primary magwell adapter housing 2500 may also include a ridged surface 2540 configured to engage a corresponding channel 2145 on the interior sidewall 2135 of the primary magazine catch body 2100 when the primary magazine adapter 200 is assembled.

When the primary magazine adapter 200 is assembled, forward movement of the primary mag catch release hook 2300 causes the ramped surface associated with the mag catch engagement feature 2340 to engage the catch arm actuation feature 2250 the ramped surface in this example) to thereby move the primary magazine catch arm 2200 away from primary mag catch release hook 2300 as well as away from the primary magazine catch body 1100. Such movement causes the primary magazine catch arm 2200 to rotate about the first end 2210 and thereby rotate the primary magazine catch arm 2200 from the first, magazine-engaged position toward the second, magazine disengaged position. Similarly, when the primary mag catch release book 2300 moves in the opposite direction, the primary magazine catch arm 2200 rotates toward the first, magazine-engaged position.

As shown in the FIG. 2A, the primary magazine catch body includes a plurality of alignment surfaces associated therewith. In at least one example, the front portion 2110, the rear portion 2115, and/or the bottom portion 2125 have a ridge or ridges formed about at least a portion of the perimeter thereof. The rear portion 2115 may also include a guide protrusion 2150. The primary magazine catch body 2100 also includes or has coupled thereto a primary latch tab 2155 coupled to or associated with the interior sidewall 2135. In at least one example, the primary latch tab 2155 may be a resilient arm 2160 with a protrusion 2165 extending, therefrom as shown.

When the primary magazine adapter 200 is properly positioned relative to the primary magazine well 1430 (FIG. 1B), movement of the primary magazine catch arm 2200 allows a magazine to be retained or released as desired from the primary magazine well. The coupling of the primary magazine adapter 2200 to the primary magazine well 1430 (FIG. 1B) will now be discussed, followed by a discussion of the coupling of the primary magazine adapter to the primary magazine release.

As shown in FIG. 1B, the primary magazine well 1430 may have an adapter-receiving portion 1440 formed by an adapter receiving recess 1432 defined in the primary magazine well 1430. The adapter-receiving portion 1440 is configured to have a plurality of magazine adapters coupled thereto, including the primary magazine adapter 200 shown. In the illustrated example, the adapter-receiving portion 1440 has a shape corresponding to the shape of the primary magazine catch body 2100 (FIG. 2A). In such an example, the adapter-receiving portion 1440 includes a from portion 1442, a rear portion, 1444, and a bottom portion 1446. One or more of the front, bottom, or rear portions (1442, 1444, 1446) of the adapter receiving portion 1440 may include guide surfaces 1448 formed thereon. In at least one example, the guide surfaces 1448 are configured to help guide coupling of a magazine adapter to the primary magazine well.

In at least one example, the guide surfaces 1448 form a latch engaging channel defined in the adapter-receiving portion 1440. Such guide surfaces 1448 may include ridges defining channels configured to receive the primary magazine catch body 2100. Further, the guide surfaces may defined a latch engaging channel 1452 configured to receive a latch to (such as primary latch tab 2155) associated with each magazine adapter to secure each magazine adapter in place relative to the primary magazine well 1430 when each magazine adapter is coupled to the primary magazine well 1430.

As shown in FIG. 2B, when the primary magazine adapter 200 is coupled to the rear portion 1420, the primary magazine catch body 2100 is retained by guide surfaces 1448 (FIG. 1B). Further, a slot 1450 defined in the adapter-receiving portion 1440 (FIG. 1B) engages the protrusion 2165 adjacent the rear portion 1444 of the adapter receiving portion 1440 and the latch engaging channel of the guide surfaces 1448 (best seen in FIG. 1B) in particular to thereby retain the primary magazine adapter 200 in place relative to the primary magazine well 1430.

As the primary magazine adapter 200, and the primary magazine catch body 2100 in particular, is moved into position relative to the primary magazine well 1430, the primary latch tab 2155 is compressed as it is urged into the latch engaging channel defined by the guide surfaces 1448 (best seen in FIG. 1B). When the primary magazine catch body 2100 is in position with the latch engaging channel 1452, the protrusion 2165 may deflect into position by moving into the corresponding slot 1450 defined in the latch engaging channel defined by the guide surfaces 1448, thereby locking the primary magazine catch body 2100 (and thus the primary magazine adapter 200) in place relative to the primary magazine well 1430. As the primary magazine adapter 200 is coupled to the primary magazine well 1430, the primary magazine adapter 200 also couples to the magazine retention/release assembly 300, as will now be discussed in more detail.

Now referring to FIG. 1B, the primary magazine well 1430, and the adapter receiving portion 1440 thereof in particular, are configured to facilitate coupling of various types of magazine types to the primary magazine well With such magazine adapters in place, the magazine retention/release assembly 300 may be manipulated to release the magazine 1500.

Now referring to FIG. 3, the exemplary magazine release/retention assembly 300 shown generally includes a rear magazine release mechanism 3000 and a forward magazine release mechanism 3100. As shown in FIG. 3, the rear magazine release mechanism 3000 includes a primary release lever 3010 and a rear transfer link 3020. The rear release lever 3010 is coupled to the stock assembly 1400 (FIG. 1B), such as to rear portion 1420, and particularly to the primary magazine well 1430. The rear release lever 3010 includes a first end 3011 and a second end 3012. A pivot hole 3014 is defined in the rear release lever 3010 between the first and second ends 3011, 3012. In the illustrated example, the rear release lever 3010 is pivotingly coupled to a front portion 1434 of the primary magazine well 1430 via a pivot pin 3028.

Such a configuration allows the second end 3012 of the rear release lever 3010 to move in a forward direction when the first end 3011 of the rear release lever 3010 is urged rearward. In some examples, a biasing member 3030 is coupled to the rear release lever 3010 which exerts a biasing force on the rear release lever 3010 to move the first end 3011 of the rear release lever 3010 forward and thus the second end 3012 of the rear release lever 3010 rearward. In at least one example, such the biasing member 3030 is a torsional spring through it will be appreciated that any type of biasing member may be utilized as desired.

The rear release lever 3010 is coupled to the rear transfer link 3020. Particularly, the rear transfer link 3020 has a first end 3021 and a second end 3022. The first end 3021 is configured to couple to the second end 3012 of the rear release lever 3010 in such a manner that axial movement (forward and rearward) of the second end 3012 of the rear release lever 3010 results in similar axial movement of the first end 3021 of the rear transfer link 3020.

The second end 3012 of the rear release lever 3010 may include a pivot post 3016 configured to be at least partially received within a post-receiving recess 3024 defined in the first end 3021 of the rear transfer link 3020. In the example shown in FIG. 3, the rear transfer link 3020 is positioned at least partially within a rear transfer link guide channel 1460 formed in the rear portion 1420 of the stock assembly 1420 (FIG. 1B). Such a configuration allows the rear transfer link 3020 to translate within the rear transfer link guide channel 1460 in response to actuation of the rear release lever 3010 such that forward movement of the first end 3021 of the rear transfer link 3020 results in forward movement of the second end 3022 of the rear transfer link 3020.

The second end 3022 of the rear transfer link 3020 is configured to couple to the first end 2310 of the primary nag catch release hook 2300 (FIG. 2A). In one example, the second end 3022 of the rear transfer link 1020 includes a post 3026 or other protrusion. As previously introduced and as shown in FIG. 2A, the primary magazine adapter 200 includes a primary mag catch release hook 2300 having a first end 2310 including a release engagement feature 2330. With reference to FIG. 2A and FIG. 3, the release engagement feature 2330 defines a slot. When the primary magazine adapter 200 is coupled to the rear portion 1420 of the stock assembly (1400, FIG. 1B), the primary magazine adapter 200 couples to the rear magazine release mechanism 3000. in particular, the release engagement feature 2330 is configured to at least partially receive the post 3026 associated with the second end 3022 of the rear transfer link 3020.

Specifically, the first end 2310 of the primary mag catch release hook 2300 (and the release engagement feature 2330 in particular) couples to the second end 3022 of the rear transfer link 3020 (and the post 3026 in particular), while the rear transfer link 3020 is also coupled to the rear release lever 3010 as previously discussed. Accordingly, when the primary magazine adapter 200 is coupled to the rear portion 1420 of the stock assembly 1400 (FIG. 1B), the rear release lever 3010 is coupled to the primary mag catch release hook 2300 via the rear transfer link 3020. When thus coupled, movement of the rear release lever 3010 to move the first end 3011 of the rear release lever 3010 rearward moves the second end 3012 of the primary release lever forward, which moves the first end 3021 and thus the second end 3022 of the rear transfer link 3020 forward, which causes the primary mag catch release hook 2300 (FIG. 2A) to move forward as well.

Referring to FIG. 2A, forward movement of the primary mag catch release hook 2300 causes the ramped surface associated with the man catch engagement feature 2340 to act against the catch arm actuation feature 2250 (the ramped surface in this example) to thereby rotate the primary magazine catch arm 2200 from the first, magazine-engaged position toward the second, magazine disengaged position. Similarly, when the primary catch release hook 2300 moves in the opposite direction, the primary magazine catch arm 2200 is moved or allowed to move toward the first, magazine-engaged position. Accordingly, pulling the first end 3011 of the rear magazine release lever 3010 rearward (best seen in FIG. 3) acts to release primary magazine catch tab 2230.

As shown in FIG. 3, the forward magazine release mechanism 3100 is coupled to the rear magazine release mechanism 3000 via a forward transfer link 3110. It will be appreciated that while the forward magazine release mechanism 3100 is discussed as being coupled to the rear portion 1420, it will be appreciated that it may be coupled or integrated with the receiver 1100 (FIG. 1B), other components and combinations thereof. The forward magazine release mechanism 3100 in the illustrated example includes an ambidextrous release bar 3120 (sometimes referred to as a mag button toggle) coupled to the rear portion 1420 at a location adjacent the trigger 1310 and/or distal to the primary magazine release mechanism 3000 and the rear release lever 3010 in particular.

As shown in FIG. 3, the forward magazine release mechanism 3100 includes an ambidextrous transfer link 3130 (sometimes referred to as a mag button toggle) configured to interact with the ambidextrous release bar 3120 to operate the forward magazine release mechanism 3100. Particularly, the forward magazine release mechanism 3100 is configured to translate lateral movement of the ambidextrous release bar 3120 into axial movement of the forward transfer link 3110.

In the illustrated example, the ambidextrous release bar 3120 includes first and second ends 3121, 3122. When the firearm 100 (FIG. 1A) is assembled, the first and second ends 3121, 3122 are positioned within the rear portion 1420 and are adjacent or extend through corresponding first and second secondary release mechanism openings 1481, 1482 (best seen in FIG. 2B) defined in the opposing walls of the rear portion 1420. The ambidextrous release bar 3120 also includes a slot 3124 defined therein between the first and the second ends 3121, 3122 thereof. The ambidextrous release bar 3120 may include a first ramped surface 3124 and a second ramped surface 3128 defining the slot 3124.

The ambidextrous transfer link 3130 includes a first arm 3132 and a second arm 3134. The ambidextrous transfer link 3130 also includes a pivot 3134 formed between the first arm 3132 and the second arm 3134. The first arm 3132 is configured to be received within the slot 3124 defined in the ambidextrous release bar 3120 to contact the ramped surfaces 3126, 3128. Contact between the ramped surfaces 3126, 3128 and the first arm 3132 cause the ambidextrous transfer link 3130 to pivot about a pin 3140 coupling the ambidextrous transfer link 3130 to the rear portion 1420.

In particular, as the ambidextrous release bar 3120 moves laterally, the first arm 3132 moves downwardly due to contact between the first arm 3132 and one of the ramped surfaces 3126, 3128. Particularly, if the ambidextrous release bar 3120 is moved right the first arm 3132 moves through contact with the first ramped surface 3126.

In the illustrated example, an angle is formed between the first arm 3132 and the second arm 3134 such that as the first arm 3132 moves downwardly, the second arm 3134 moves generally in a forward direction. The second arm 3134 is coupled to the rear magazine release mechanism 3000 and the second end 3012 of the rear release lever 3010 in particular via the forward transfer link 3110.

In the illustrated example, the forward transfer link 3110 may be a cable coupled to each of the second arm 3134 and the second end 3012 of the rear release lever 3010. In such an example, forward movement of the second arm 3134 results in forward movement of the second end 3012 of the rear release lever 3010 due to their coupling with the forward transfer link 3110. As previously discussed, forward movement of a second end 3012 of the rear release lever 3010 causes the rear transfer link 3020 to move forward as well. As discussed elsewhere herein, the rear transfer link 3020 couples to either the primary magazine adapter 200 or the secondary magazine adapter 400 (FIG. 4A) via the primary mag catch release hook 2300 or a secondary mag catch release hook 4300 (FIG. 4A) respectively.

As discussed elsewhere herein, when the rear transfer link 3020 is thus coupled to the primary magazine adapter 200 or the secondary magazine adapter 400 (FIG. 4A movement of the rear transfer link 3020 acts to move a corresponding magazine catch arm 2200 or 4200 (FIG. 4A) between a first, magazine-engaged position and a second, magazine disengaged position. Accordingly, the coupling of the forward magazine release mechanism to the rear magazine release mechanism thereby allows the forward magazine release mechanism to also move a corresponding magazine catch arm 2200 or 4200 (FIG. 4A) between a first, magazine position and a second, magazine disengaged position.

The biasing member 3030 exerts a biasing force on the rear release lever 3010 that urges the second end 3012 rearwardly. In at least one example, another biasing member 3150 acts on the ambidextrous transfer link 3130 to urge the first arm 3132 into contact into engagement with the ramped surfaces 3126, 3128 associated with the ambidextrous release button 3120. Such a force thereby acts to move the ambidextrous release bar 3120 toward a center position with respect to the rear portion 1420 while also urging the second arm rearwardly.

In some examples, such biasing force is supplemented by a tension force acting on the forward transfer link 3110 via the second end 3012 of the rear release lever 3010 by the biasing member 3030 that urges the second end 3012 of the rear release lever 3010 rearwardly. Accordingly, magazines release operations may be performed using retention/release mechanisms at multiple locations along the length of the firearm.

Referring now to FIG. 2B, each magazine adapter is configured to cooperate with the primary magazine well 1430 to allow the type of magazine corresponding to the magazine type of the magazine adapter to be coupled to and released from the firearm 100 (FIG. 1A). In the case of the primary magazine, adapter 200, when coupled to the primary magazine well 1430, the combination of the primary magazine well 1430 and the primary magazine adapter 200 define a primary magazine well opening 2600 configured to receive the primary type of magazine 1500 (FIG. 1B). Particularly, as previously introduced, each magazine adapter includes a magwell adapter housing. In the case of the primary magazine adapter 200, the primary magwell adapter housing 2500 is configured to be coupled to a second, interior portion 2135 (FIG. 2A) of the primary magazine catch body 2100 (both best seen in FIG. 2A).

In the illustrated example, the second portion 2520 of the primary magwell adapter housing 2500 is configured to cooperate with the primary magazine well 1430 to allow a primary-type magazine 1500 (seen in FIG. 1B) to be coupled to the firearm 100 (also best seen in FIG. 1B).

In the illustrated example, the primary magazine well 1430 may be configured to accept the hugest type of magazine the firearm 100 is able to accommodate with respect to either maximum width, maximum length or some combination of those or other dimensions. Such magazines will be referred to herein as primary-type magazines. In the illustrated example, the primary magazine well 1430 is configured to accommodate 0.308 double stack magazines (such as AR-10 magazines). As introduced, the primary magazine adapter 200 is also configured to retain a primary magazine 1500 (FIG. 1B) in place relative to firearm and to cooperate with the magazine release/retention assembly 300 to allow removal of such primary magazines.

As will be discussed in more detail herein, a magazine adapter(s) may be utilized to allow the firearm 100 (FIGS. 1A-1B) to accept different magazines. By also changing the barrel 1200 and action 1300, to the barrel 5200 and action 5300 shown in FIG. 5A, the same receiver 1100, stock assembly 1400, and controls associated with the receiver 1100 (such as the trigger 1310 and the magazine retention/release assembly 300) may be used to fire different types of cartridges.

As previously discussed, the primary magazine well 1430 may be formed with or coupled to the stock assembly 1400, the receiver 1100, or some other component. In the illustrated example, the primary magazine well 1430 is part of or coupled to the primary magazine release/retention assembly 300.

Referring to FIG. 2B, the primary magazine well 1430 defines a primary magazine well opening 2600. The interior of the primary magazine well 1430 has a profile that corresponds closely with the exterior profile of a primary-type magazine 1500 (FIG. 1A), especially when the primary magazine adapter 200 is coupled to the primary magazine well 1430.

The interior of the primary magazine well 1430 includes a front portion 1462, opposing first and second side portions 1464, 1466, and a rear portion 1468. In at least one example, the adapter receiving portion 1440 described above is part of the first side portion 1464. The inner surfaces 1462A, 1464A, 1466A, 1468A of these portions 1462, 1464, 1466, 1468 form a partial magazine receiving enclosure 1700 (FIG. 1B). Particularly, since a portion of first side portion 1464 has the adapter receiving recess 1432 (FIG. 1B) defined therein, the enclosure formed by the inner surfaces 1462A, 1464A, 1466A, 1468A is partial in that the adapter receiving recess 1432 defines a gap between the front portion 1442 and the rear portion 1444 (best seen FIG. 1B), When the primary adapter 200 is coupled to the primary magwell, the second portion 2520 (inner surface in this case) of the primary magwell adapter housing 2500 fills in at least a portion of such a gap, thereby forming a primary magazine receiving enclosure 1710 as shown in FIG. 1B. The primary magazine receiving enclosure 1710 defines the primary magazine well opening 2600 and forms the profile set forth above. Such a magazine receiving enclosure 1710 may include gaps therebetween provided the magazine receiving enclosure allows the primary magazine adapter 200 to cooperate with the primary magazine well 1430 (FIG. 1B) to selectively couple and decouple a primary-type magazine, such as magazine 1500 (FIG. 1B) to the firearm 100 (FIG. 1B).

The combined length of the first inner surface 1464A and the second portion 2520 and/or the length of the second inner surface 1466A may correspond closely to the length of the sidewalls 1520, 1525 of the magazine 1500 (a primary-type magazine, FIG. 1B) to allow a close sliding fit or even a slight interference fit. Similarly, the width of the inner surfaces 1462A, 1468A of the front portion 1462 and the rear portion 1468 correspond closely to the width of the front, and rear portions 1530, 1540 of the magazine 1500 (FIG. 1B) to allow the close sliding fit or slight interference fit between the magazine 1500 and the primary magazine well 1430. Accordingly, the inner shape of the primary magazine well 1430 defining the primary magazine well opening 2600 corresponds closely to the outer shape of the magazine 1500 (in this case, a primary-type magazine.

FIG. 4A illustrates a secondary magazine adapter 400. As shown in the FIG. 4A, the secondary magazine adapter 400 includes a secondary magazine catch assembly 4000 and a secondary magwell adapter housing 4500. The secondary magazine catch assembly 4000 generally includes a secondary magazine catch body 4100, a secondary magazine catch arm 4200, and a secondary mag catch release hook 4300.

The secondary magazine catch body 4100 is configured to couple to the secondary magazine well 1430 (FIG. 1B). The secondary magazine catch body 4100 may be of any desired shape. In the illustrated example, the secondary magazine catch body 4100 includes a front portion 4110, a rear portion 4115, a top portion 4120, a bottom portion 4125, a first or exterior sidewall 4130, and second or interior sidewall 4135. It will be appreciated the secondary magazine catch body 4100 may have any shape desired. A mag catch opening 4140 is formed in the secondary magazine catch body 4100 that defines an opening that extends through the first and second sidewall 4130, 4135 respectively.

The secondary magazine catch body 4100 is configured to allow the secondary magazine catch arm 4200 to move between a first, magazine engaging position to a second, magazine disengaging position. In the illustrated example, the secondary magazine catch arm 4200 rotates between these positions. Accordingly, the secondary magazine catch arm 4200 may include a first end 4210 pivotingly coupled to the secondary magazine catch body 4100. In particular, a pin 4400 extends through holes 4112 defined in the first end 4110 of the secondary magazine catch body 4100 and corresponding holes 4212 in the first end 4210 of the secondary magazine catch arm 4200.

The secondary magazine catch arm 4200 may also include a second end 4220 having a secondary magazine catch tab 4230 associated therewith. In such an example, the secondary magazine catch arm 4200 may be configured to rotate to thereby allow the second end 4220 of the magazine catch arm 4200 to rotate to allow the secondary magazine catch tab 4230 to extend through the secondary magazine catch opening 4140. The position of the secondary magazine catch tab 4230 extending through the secondary magazine catch opening 4140 and extending beyond the second sidewall 4135 in particular may correspond to the first, magazine engaging position introduced above. A biasing member 4240 may be included with the secondary magazine catch assembly 4000 to exert a biasing force on the secondary magazine catch arm 4200 to help maintain the secondary magazine catch arm 4200 (and the secondary magazine catch tab 4230 in particular) in the first, magazine engaging position.

As shown in FIG. 4A, the secondary magazine catch arm 4200 further includes at least one catch arm actuation feature 4250 configured to transfer and/or translate inputs received from the magazine retention/release assembly 300 (FIG. 3) into appropriate movement of the secondary magazine catch arm 4200 from the first, magazine-engaged position toward the second, magazine disengaged position and from the second, disengaged position back toward the first, magazine disengaged.

In one example, the catch arm actuation feature 4250 includes a ramped surface positioned between the first and second ends 4210, 4220 of the secondary magazine catch arm 4200. The ramped surface may be configured to interact with the secondary mag catch release hook 4300.

The secondary mag catch release hook 4300 may include a first end 4310 and a second end 4320. The first end 4310 of the secondary mag catch release hook 4300 may include a release engagement feature 4330 configured allow the mag catch release hook 4300 to be selectively coupled and uncoupled to the magazine retention/release assembly 300, as will be described at an appropriate point hereinafter in more detail.

The second end 4320 of the secondary mag catch release hook 4300 includes a mag catch engagement feature 4340. The mag catch engagement feature 4340 is configured to engage the catch arm actuation feature 4250 in such a manner that translation of the secondary mag catch release hook 4300 moves the secondary magazine catch arm 4200 between the first, magazine-engaged position and the second, magazine disengaged position.

The secondary mag catch release hook 4300 is coupled to the secondary magazine catch body 4100 in such a manner that the mag catch engagement feature 4340 extends outwardly through the interior sidewall 4135 of the secondary magazine catch body 4100 and at least partially into a mag catch engagement feature opening 4170. It will be appreciated that in some examples, the mag catch engagement feature opening 4170 may be integral or continuous with the mag catch opening 4140.

With continued reference to FIG. 4A, the secondary magazine catch release hook 4300 is at least partially received within a hook receiving channel 4350 defined in the second or interior sidewall 4135 of the secondary magazine catch body 4100. In the illustrated example, when coupled to the secondary magazine catch body 4100, the first end 4310 of the secondary mag catch release hook 4300 extends beyond the front portion 4110 of the secondary magazine catch body 4100.

The secondary magwell adapter housing 4500 is configured to be coupled to the secondary magazine catch body 4100 and to retain the secondary mag catch release hook 4300 therebetween. in particular, the secondary magwell adapter housing 4500 generally includes a first portion 4510 configured to couple to the secondary magazine catch body 4100 and a second portion 4520 opposite the first portion 4510. For example, the first portion 4510 includes a tab 4530 having, a hole 4532 defined therein. The tab 4530 is may be positioned relative to the secondary magazine catch body 4100 to align the hole 4532 with the holes 4112, 4212 in the secondary magazine catch body 4100 and the secondary magazine catch arm 4200 respectively to allow the pin 4400 to pass therethrough thereby coupling the secondary magwell adapter housing 4500 to the secondary magazine catch body 4100.

With continued reference to FIG. 4A, the first portion 4510 of the secondary magwell adapter housing 4500 may also include a recess 4540 configured to engage a corresponding protrusion 4145 on the interior sidewall 4135 of the secondary magazine catch body 4100 when the secondary magazine adapter 400 is assembled.

In the illustrated example, forward movement of the secondary mag catch release hook 4300 causes the ramped surface associated with the mag catch engagement feature 4340 to engage the catch arm actuation feature 4250 (the ramped surface in this example) to thereby rotate the secondary magazine catch arm 4200 from the first, magazine-engaged position toward the second, magazine disengaged position. Similarly, when the secondary mag catch release hook 4300 moves in the opposite direction, the secondary magazine catch arm 4200 is moved or allowed to move toward the first, magazine-engaged position.

With continued reference to FIG. 4A, the secondary magazine catch body 4100 includes a plurality of alignment surfaces associated therewith. In at least one example, the front portion 4110, the rear portion 4115, and/or the bottom portion 4125 have a ridge or ridges formed about at least a portion of the perimeter thereof. The rear portion 4115 may also include a guide protrusion 4150. The secondary magazine catch body 4100 also includes or has coupled thereto a secondary latch tab 4155 coupled to or associated with the interior sidewall 4135. In at least one example, the secondary latch tab 4155 may be a resilient arm 4160 with a protrusion 4165 extending therefrom as shown.

When the secondary magazine adapter 400 is coupled to the rear portion 1420 of the stock assembly (1400, FIG. 1B), the primary magazine adapter 400 couples to the rear magazine release mechanism 300 (FIG. 3). In particular, the release engagement feature 4330 is configured to at least partially receive the post 3026 associated with the second end 3022 of the rear transfer link 3020 (all best seen in FIG. 3).

Accordingly, when the secondary magazine adapter 400 is coupled to the rear portion 1420 of the stock assembly 1400 (FIG. 1B), the rear release lever 3010 (FIG. 3) is coupled to the primary mag catch release hook 4300 (FIG. 4A) via the rear transfer link 3020 (also shown in FIG. 3). When thus coupled, movement of the rear release lever 3010 to move the first end 3011 of the rear release lever 3010 rearward moves the second end 3012 of the primary release lever forward, which moves the first end 3021 and thus the second end 3022 of the rear transfer link 3020 forward, which causes the primary mag catch release hook 4300 (FIG. 2A) to move forward as well.

Referring to FIG. 4A, forward movement of the secondary mag catch release hook 4300 causes the ramped surface associated with the mag catch engagement feature 4340 associated with the second end 4320 of the mag catch engagement feature 4340 to act against the catch arm actuation feature 4250 (the ramped surface in this example) to thereby rotate the primary magazine catch arm 4200 from the first, magazine-engaged position toward the second, magazine disengaged position. Similarly, when the secondary catch release hook 4300 moves in the opposite direction, the secondary magazine catch arm 4200 is moved or allowed to move toward the first, magazine-engaged position. Accordingly, pulling the first end 3011 (FIG. 3) of the rear magazine release lever 3010 rearward (best seen in FIG. 3) acts to release secondary magazine catch tab 4230.

In the illustrated example, a bolt catch relay 4700 is provided that may be part of or associated with the secondary magazine adapter 400. In such an example, the bolt catch relay 4700 is slidingly coupled to the secondary magwell adapter housing 4500 in such a manner that the bolt catch engages a corresponding portion of a follower of a secondary magazine 5000 (FIG. 5) if the secondary magazine 5000 is empty as the action cycles rearwardly (and is coupled to the firearm 100 (FIG. 5) via the secondary magazine adapter 400) thereby holding the bolt open, as is known in the art.

In particular, the bolt catch relay 4700 may generally include a post portion 4710 and a bolt catch 4720. In such an example, the post portion 4710 may be slidingly received in a bolt catch recess 4550 defined in the secondary magwell adapter housing 4500 and may be retained relative to the secondary magwell adapter housing 4500 in any suitable manner.

As shown in the FIG. 4A, the bolt catch 4720 includes a forward portion 4722 configured to extend forward of the inner surface 4568A of the rear portion 4568 (both labeled in FIG. 4B) sufficiently to engage a hold-open portion of a magazine follower. The bolt catch 4720 also includes a rear portion 4724 that extends rearwardly a sufficient distance to replicate the hold-open portion function of a primary type magazine, such as magazine 1500 (FIG. 1B). Accordingly, the rear portion 4724 of the bolt catch 4720 is positioned at the same position relative to the profile of the magwell insert that a hold open portion of as magazine follower is positioned on a primary type of magazine.

The exterior of the secondary magwell adapter housing 4500 corresponds closely to interior profile of the primary magazine well 1430 that defines the primary magazine well opening 2600 (both best seen in FIG. 1B).

Referring still to FIG. 4B, the secondary magwell adapter housing 4500 includes a front portion 4562, opposing first and second side portions 4564, 4566, and a rear portion 4568, each having outer surfaces 4562B, 4564B, 4566B, and 4568B and inner surfaces 4562A, 4564A, 4566A, 4568A respectively. The outer surfaces 4562B, 4564B, 4566B, and 4568B define an outer perimeter that corresponds closely to shape of primary magazine well 1430 that defines the primary magazine well opening 2600 (FIG. 2B) and thus also corresponds closely in shape to the shape of a primary-type magazine (such as magazine 1500, FIG. 1B).

As previously introduced, since the first side portion 1464 has the adapter receiving recess 1432 (FIG. 1B) defined therein, the enclosure formed by the inner surfaces 1462A, 1464A, 1466A, 1468A is partial in that the adapter receiving recess 1432 defines a gap between the front portion 1442 and the rear portion 1444 (best seen FIG. 1B). Some portion of the secondary magazine adapter 400, such as the first portion 4510 (FIG. 4A) of the secondary magwell adapter housing 4500 and/or the secondary magazine catch body 4100 fill in at least a portion of the gap to thereby define an second primary magazine receiving enclosure 4800. The second primary magazine receiving enclosure 4800 is similar to the primary magazine receiving enclosure 1710 (FIG. 1) and thus may include gaps therebetween provided the second primary magazine receiving enclosure 4800 allows the secondary magazine adapter 200 to cooperate with the primary magazine well 1430 (FIG. 1B) to selectively couple and decouple the secondary magazine adapter 400 to the primary magazine well 1430 (FIG. 1B).

In at least one example, the inner surfaces 4562A, 4564A, 4566A, 4568A define a complete secondary magazine receiving enclosure 4800. Further, the partial magazine enclosure 1700 (FIG. 1B) may be completed by the first portion 4510 of the secondary magwell adapter housing 4500 and/or the secondary magazine catch body 4100 (both best seen in FIG. 4A).

As illustrated in FIG. 4B, an interior profile of the secondary magwell adapter housing 4500 forms a secondary magazine enclosure 4810 thereby defining a secondary-type magazine well opening 4600 having a shape corresponding to secondary-type magazines 5500 (FIG. 5) to thereby allow secondary-type magazines 5000 (FIG. 5) to be coupled to the secondary magazine adapter 400 and thus to the firearm. Such a secondary magazine receiving enclosure 4810 may include gaps therebetween provided the secondary magazine receiving enclosure 4810 allows the secondary magazine adapter 400 to cooperate with the primary magazine well 1430 (FIG. 4B) to selectively couple and decouple a secondary-type magazine, such as magazine 5500 (FIG. 5A) to the firearm 100 (FIG. 5B).

As shown in FIG. 4B, the secondary magazine enclosure 4810 includes inner surfaces 4564A, 4566A of the first and second side portions 4564, 4566, which together define the secondary magazine well opening 4600. The secondary magazine well opening 4600 corresponds closely to the length of sidewalls 5520, 5525 of the magazine 5500 (a secondary-type magazine, FIG. 5B) to allow a close sliding fit or even a slight interference fit. Similarly, the width of the inner surfaces 4562A, 4568A of front portion 4562 and the rear portion 4568 defining the primary magazine well opening 2600 (FIG. 2B) correspond closely to the width of the front and rear portions 5530, 5540 of the magazine 5500 (FIG. 5B) to allow the close sliding fit or slight interference fit between the magazine 5500 (FIG. 5B) and the secondary magwell adapter housing 4500. Accordingly, the inner shape of the secondary magwell adapter housing 4500 defining the secondary magazine well opening 4600) corresponds closely to the outer shape of the magazine 5500 (FIG. 5B).

As shown in FIG. 4B, the secondary magazine enclosure 4810 includes inner surfaces 4564A, 4566A of the first and second side portions 4564, 4566, which together define the secondary magazine well opening 4600. The secondary magazine well opening 4600 corresponds closely to the length of sidewalls 5520, 5525 of the magazine 5500 (a secondary-type magazine, FIG. 5B) to allow a close sliding fit or even a slight interference fit. Similarly, the width of the inner surfaces 4562A, 4568A of front portion 4562 and the rear portion 4568 defining the primary magazine well opening 2600 (FIG. 2B) correspond closely to the width of the front and rear portions 5530, 5540 of the magazine 5500 (FIG. 5B) to allow the close sliding fit or slight interference fit between the magazine 5500 (FIG. 5B) and the secondary magwell adapter housing 4500. Accordingly, the inner shape of the secondary magwell adapter housing 4500 defining the secondary magazine well opening 4600) corresponds closely to the outer shape of the magazine 5500 (FIG. 5B).

In such an example, the secondary magazine adapter 400 is configured to accept secondary magazine types, such as magazine 5500. The secondary magazine adapter 400 may be configured to accept any types of magazines, such as SR25, 7.62×39, 5.56×45/.223 Rem., 6.8SPC, 5.45×39, 300 Blackout, or any other type of magazines that are smaller than or equal to primary-type magazines (such as magazine 1500) with respect to width and length.

It will be appreciated that larger or smaller types of primary magazine wells and thus magazines are also contemplated by this disclosure and thus any types of magazine adapters and magazines are also contemplated.

Firearms are provided herein having at least one magazine adapter that will be described in more detail below and may include a magazine retention/release assembly that utilizes a plurality of magazine release mechanisms. Firearms may also accept multiple magazine adapters, which allows the firearm to use multiple calibers and to readily switch between calibers while using the same controls (such as the same trigger and magazine retention/release assembly) in the same configuration, which may make the firearm readily adaptable according to operator preferences or requirements with minimal additional training. Further, as will be discussed in more detail herein, multiple magazine release mechanisms may allow the operator to leverage training on other systems as one of the magazine retention/release mechanisms may be at a familiar location relative to the trigger and/or other components, such as the grip.

As used herein, forward means toward the muzzle of the rifle while rearward means toward the buttstock or away from the muzzle of the rifle. Default orientation of firearms are referenced to positions of the firearm when barrel is generally parallel to the ground or other horizontal planar support and a central plane passing through the firearm is generally vertical relative to the supports described. The term “upper” refers to those components most distal the ground or other generally planar, horizontal support when thus oriented while lower refers to those components more proximal the ground or other horizontal support. Such an orientation is for reference and does not constrain operation of the firearm.

The parts and components described herein may be formed of any suitable method using any suitable material. Suitable materials include, without limitation, plastics, composites, metallic materials and alloys. Suitable methods include, without limitation, 3D printing, machining, casting, molding, and other processes. 

What is claimed is:
 1. A firearm, comprising: a magazine well including an adapter-receiving portion defining an adapter receiving-recess; and a magazine adapter removably coupled to the adapter-receiving portion of the magazine well, the magazine adapter including a magazine, catch assembly configured to move between a magazine-engaging state and as magazine-disengaging state.
 2. The firearm of claim 1, wherein the magazine well includes a front portion, a rear portion, and first and second opposing side portions, the front portion, the rear portion, and the first and the second opposing side portions forming a first portion of a magazine receiving enclosure.
 3. The firearm of claim 2, wherein the magazine adapter further includes a magwell adapter housing coupled to the magazine catch assembly, the magwell adapter housing forming a second portion of the magazine receiving enclosure when the magazine adapter is coupled to the magazine well.
 4. The firearm of claim 3, wherein the magwell adapter housing is at least partially received within the adapter-receiving recess defined by the adapter-receiving portion.
 5. The firearm of claim 3, wherein the first portion of the magazine receiving enclosure and the second portion of the magazine receiving enclosure comprise a first magazine receiving enclosure.
 6. The firearm of claim 3, wherein the magwell adapter housing further includes a first portion and a second portion, wherein the magazine receiving enclosure comprises a first magazine receiving enclosure including the first portion of the magwell adapter housing, and wherein the second portion of the magwell adapter housing comprises a second magazine receiving enclosure.
 7. The firearm of claim 6, wherein the second magazine enclosure is contained within the first magazine enclosure.
 8. The firearm of claim 6, wherein at least part of the magazine adapter is at least partially received within the adapter-receiving recess defined by the adapter-receiving portion.
 9. The firearm of claim 1, wherein the magazine adapter includes a magazine catch body, a magazine catch arm pivotingly coupled to the magazine catch body, and a magazine catch release hook coupled to the magazine catch body and the magazine catch arm, wherein translation of the magazine catch release hook causes the magazine catch arm to pivot relative to the magazine catch body, wherein such pivoting moves the magazine catch assembly being between the magazine-engaging state and the magazine-disengaging state.
 10. The firearm of claim 1, wherein at least a portion of the magazine adapter further is received within the adapter-receiving recess defined by the adapter-receiving portion.
 11. A firearm, comprising: a magazine release/retention assembly, including: a first magazine release mechanism including: a first release lever having a first end and a second end; a first transfer link coupled to the second end of the first release lever, the first transfer link being configured to removably couple to a magazine catch assembly, the magazine catch assembly being configured to move between a magazine-engaging state and a magazine-disengaging state, wherein actuation of the first release lever moves the magazine catch assembly toward the magazine-disengaging state and wherein release of the first release lever returns the magazine catch assembly to the magazine-engaging state; and a second magazine release mechanism, including an ambidextrous transfer link, an ambidextrous release bar coupled to ambidextrous transfer link, and a second transfer link coupling the ambidextrous transfer link to the first transfer link and the first release lever such that actuation of the ambidextrous release bar moves the magazine catch assembly toward the magazine-disengaging state and wherein release of the ambidextrous release bar returns the magazine catch assembly to the magazine-engaging state.
 12. The firearm of claim 11, wherein the first magazine release mechanism is a rear magazine release mechanism and the second magazine release mechanism is a forward release mechanism.
 13. The firearm of claim 11, wherein the first release lever is actuated by pivoting the first release lever about a pivot between a first end of the first release lever and a second end of the first release lever.
 14. The firearm of claim 13, wherein pivoting the first release lever results in axial movement of the first transfer link.
 15. The firearm of claim 14, wherein actuating the ambidextrous release bar includes laterally moving the ambidextrous release bar.
 16. The firearm of claim 15, wherein lateral movement of the ambidextrous release bar results in axial movement of the second transfer link.
 17. The firearm of claim 11, wherein the ambidextrous release bar includes a first ramped surface and a second ramped surface, the first and second ramped surfaces defining a slot and wherein the ambidextrous transfer link is at least partially received within the slot.
 18. The firearm of claim 11, wherein the magazine catch assembly includes a magazine catch hook configured to at least partially receive a post coupled to the first release lever.
 19. The firearm of claim 18, wherein the magazine catch release hook is part of a magazine adapter and wherein the magazine adapter further includes a magazine catch body, and a magazine catch arm pivotingly coupled to the magazine catch body, wherein the magazine catch release hook coupled to the magazine catch body and the magazine catch arm such that axial translation of the magazine catch release hook causes the magazine catch arm to pivot relative to the magazine catch body, wherein such pivoting moves the magazine catch assembly between the magazine-engaging state and the magazine-disengaging state.
 20. The firearm of claim 19, further comprising a magazine well, wherein the magazine adapter is removably coupled to the magazine well.
 21. A firearm, comprising: a magazine well including an adapter-receiving portion defining an adapter receiving-recess; and a magazine adapter configured to selectively retain a type of magazine in the magazine well, including a magazine catch assembly removably coupled to the adapter-receiving portion of the magazine well, the magazine catch assembly being configured to move between a magazine-engaging state and a magazine-disengaging state; and a magazine release/retention assembly, including: a first magazine release mechanism including: a first release lever having a first end and a second end; a first transfer link coupled to the second end of the first release lever, the first transfer link being configured to removably couple to the magazine catch assembly, wherein actuation of the first release lever moves the magazine catch assembly toward the magazine-disengaging state and wherein release of the first release lever returns the magazine catch assembly to the magazine-engaging state; and a second magazine release, mechanism, including an ambidextrous transfer link, an ambidextrous release bar coupled to ambidextrous transfer link, and a second transfer link coupling the ambidextrous transfer link to the first transfer link and the first release lever such that actuation of the ambidextrous release bar moves the magazine catch assembly toward the magazine-disengaging state and wherein release of the ambidextrous release bar returns the magazine catch assembly to the magazine-engaging state.
 22. The firearm of claim 20, wherein the magazine well includes a front portion, a rear portion, and first and second opposing side portions, the front portion, the rear portion, and the first and the second opposing side portions forming a first portion of a magazine receiving enclosure, and wherein magazine adapter further includes a magwell adapter housing coupled to the magazine catch assembly, the magwell adapter housing forming a second portion of the magazine receiving enclosure when the magazine adapter is coupled to the magazine well. 